White light emitting diode module

ABSTRACT

Disclosed is a white light emitting diode module including a conducting wire frame, a first primary color chip, a second primary color chip and a phosphor layer. The conducting wire frame has an accommodating groove. The first primary color chip is installed at the bottom of the middle of the accommodating groove, and the first primary color chip transmits a first light emitting source with a wavelength λ 1 . The second primary color chip is stacked on top of the first primary color chip and the second primary color chip transmits a second light emitting source with a wavelength λ 2 . The phosphor layer is formed on the second primary color chip and excited to produce a fluorescent light with a wavelength λ 3 . Therefore, the stacked LED chips and the phosphor can be used to obtain a white light source with high color saturation.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority under 35 U.S.C. §119(a)on Patent Application No(s). 101143915 filed in Taiwan, R.O.C. on Nov.23, 2013, the entire contents of which are hereby incorporated byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of illumination, and moreparticularly to a white light emitting diode module capable of using astacked double chip to mix red phosphor to achieve high colorsaturation.

2. Description of the Related Art

Since light emitting diode (LED) has the advantages of low workingvoltage, small power consumption, high stability, long life, strongimpact and vibration resistance, light weight, small volume and lowcost, therefore the LED has been used extensively in many areas. Indaily life, most of us use white light lamps for indoor illumination, sothat the study of white light emitting diode has become an importantsubject.

At present, there are two main methods of producing a white LED asdescribed below. 1. A combination of red, green and blue LEDs is used toproduce a mixed light to obtain a white light source. 2. An LED lightsource is used to excite an illuminescent material to produce whitelight. For example, a blue LED together with phosphor that producesyellow light, or a blue LED together with two kinds of phosphors thatproduce green light and red light respectively, or a purple orultraviolet LED that excites red, green and blue phosphors is used forproducing white light.

Wherein, three chips (RGB) are packaged into an LED set. Although thewhite light produced by mixed lights has a relatively large color gamutand a good mixing light efficiency, the driving current of each chip canbe adjusted freely to produce different colors. However, it is not easyto control the proportion of red, green and blue mixing lights, and theextent of the light emitting efficiency of each color being affected bytemperature varies, and the life cycle of different chips varies, andthe manufacturing cost is high, so that the aforementioned white lightmixing method is not popular in the application of illumination.

Although the way of using a blue LED to excite yellow phosphor canproduce white light, the chromaticity of the produced white light ispoor and cannot be compared with the conventional incandescent lamp andcold cathode fluorescent lamp (CCFL). In addition, the way of using anultraviolet LED to excite red, green and blue fluorescent lights toproduce white light can produce a white light with high chromaticity.Since the light emitting efficiency of the ultraviolet LED is low andthe ultraviolet power is high and the packaging material of LED may beaged easily, therefore this method cannot be applied in generalillumination or a backlight modules.

Therefore, it is an urgent subject for the market to provide a design ofa white light emitting diode module capable of simplifying the wirebonding process, lowering the cost, providing high color saturation, andimproving the white light mixing effect.

SUMMARY OF THE INVENTION

In view of the problems of the prior art, it is a primary objective ofthe present invention to overcome the problems by providing a whitelight emitting diode module with high color saturation, so as to improvethe white light mixing effect and achieve the effects of simplifying thewire bonding process and lowering the cost.

To achieve the aforementioned objective, the present invention providesa white light emitting diode module comprising a conducting wire frame,a first primary color chip, a second primary color chip and a phosphorlayer. The conducting wire frame has an accommodating groove. The firstprimary color chip is installed at the bottom of the middle of theaccommodating groove and has a light emitting surface area A₁, and thefirst primary color chip transmits a first light emitting source with awavelength λ1, and 380 nm≦λ1≦70 nm. The second primary color chip isstacked on top of the first primary color chip and has a light emittingsurface area A2, and the second primary color chip transmits a secondlight emitting source with a wavelength λ2, and 500 nm≦λ2≦550 nm. Thephosphor layer is formed on the second primary color chip and excited toproduce a fluorescent light with a wavelength λ3, and 600 nm≦λ3≦670 nm.Wherein, the light emitting surface areas of the first primary colorchip and the second primary color chip satisfy the following relation:

0.5≦A1/A2≦2.

To achieve the aforementioned objective, the present invention providesa white light emitting diode module, comprising a conducting wire frame,a first primary color chip, a second primary color chip and a phosphorlayer. The conducting wire frame has an accommodating groove. The firstprimary color chip is installed at the bottom of the middle of theaccommodating groove and has a light emitting surface area A1, and thefirst primary color chip transmits a first light emitting source with awavelength λ1, and 500 nm≦λ2≦550 nm. The second primary color chip isstacked on top of the first primary color chip and has a light emittingsurface area A2, and the second primary color chip transmits a secondlight emitting source with a wavelength λ2, and 380 nm≦λ1≦470 nm. Thephosphor layer is formed on the second primary color chip and excited toproduce a fluorescent light with a wavelength λ3, and 600 nm≦λ3≦670 nm.Wherein, the light emitting surface areas of the first primary colorchip and the second primary color chip satisfy the following relation:

0.5≦A1/A2≦2.

Wherein, there are different implementation modes of the phosphor layerin the present invention, and the phosphor layer can be formed in theaccommodating groove and covered onto the first primary color chip andthe second primary color chip, or coated and encapsulated on the firstprimary color chip and the second primary color chip, or the phosphorlayer is attached onto the second primary color chip having a lightemitting surface area A3 and the primary color chips. Wherein, the lightemitting surface area A₂ of the second primary color chip and the lightemitting surface area A₃ of the phosphor plate satisfy the followingrelation:

0.8≦A3/A2≦1.

In addition, the first primary color chip and the second primary colorchip are coupled to positive and negative electrodes of the conductingwire frame by the plurality of conducting wires respectively, or thefirst primary color chip has a plurality of bumps attached in theaccommodating groove of the conducting wire frame, and the secondprimary color chip is coupled to the positive and negative electrodes ofthe conducting wire frame by the plurality of conducting wires.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of a white light emitting diode module of afirst preferred embodiment of the present invention;

FIG. 2 is a schematic view of a white light emitting diode module of asecond preferred embodiment of the present invention;

FIG. 3 is a schematic view of a white light emitting diode module of athird preferred embodiment of the present invention;

FIG. 4 is a schematic view of a white light emitting diode module of afourth preferred embodiment of the present invention;

FIG. 5 is a schematic view of a white light emitting diode module of afifth preferred embodiment of the present invention;

FIG. 6 is a schematic view of a white light emitting diode module of asixth preferred embodiment of the present invention;

FIG. 7 is a schematic view of a white light emitting diode module of aseventh preferred embodiment of the present invention;

FIG. 8 is a schematic view of a white light emitting diode module of aneighth preferred embodiment of the present invention;

FIG. 9 is a schematic view of a white light emitting diode module of aninth preferred embodiment of the present invention; and

FIG. 10 is a schematic view of a white light emitting diode module of atenth preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The technical content of the present invention will become apparent withthe detailed description of preferred embodiments and the illustrationof related drawings as follows.

With reference to FIG. 1 for a schematic view of a white light emittingdiode module of the first preferred embodiment of the present invention,the white light emitting diode module 1 comprises a conducting wireframe 11, a first primary color chip 12, a second primary color chip 13and a phosphor layer 14. The conducting wire frame 11 has anaccommodating groove. Wherein, the conducting wire frame 11 iselectroplated to enhance the resistance of surface corrosion and thesolderability after the stamping process of metal, and finally formed byplastic injection molding, wherein the metal includes but not limited toa copper alloy.

The first primary color chip 12 and the second primary color chip 13 area blue LED chip and a green LED chip respectively, wherein the firstprimary color chip 12 is installed at the bottom of the accommodatinggroove of the conducting wire frame 11, and the first primary color chip12 has a light emitting surface area A₁, and the first primary colorchip 12 transmits a first light emitting source with a wavelength and380 nm≦λ₁≦470 nm. The second primary color chip 13 is stacked on top ofthe first primary color chip 12 and has a light emitting surface areaA₂, and the second primary color chip 13 transmits a second lightemitting source with a wavelength λ₂, and 500 nm≦λ₂≦550 nm.

The ratio of the light emitting surface area A₁ of the first primarycolor chip 12 to the light emitting surface area A₂ of the secondprimary color chip 13 of the white light emitting diode module 1 is0.5≦A₁/A₂≦2. In this preferred embodiment of the present invention, theratio of the light emitting surface area A₁ of the first primary colorchip 12 to the light emitting surface area A₂ of the second primarycolor chip 13 preferably 0.5≦A₁/A₂<1.

Wherein, the first primary color chip 12 and the second primary colorchip 13 are coupled to positive and negative electrodes of theconducting wire frame 11 by a plurality of conducting wires 121, 131respectively. Preferably, the conducting wires 121, 131 are gold wires.

The phosphor layer 14 is filled and disposed in an accommodating grooveof the conducting wire frame 11 and covered onto the first primary colorchip 12 and the second primary color chip 13, and excited to produce afluorescent light with a wavelength λ₃, and 600 nm≦λ₃≦670 nm.

Preferably, the wavelength λ₁ of the first light emitting source is 450nm≦λ₁≦452 nm, the wavelength λ₁ of the second light emitting source is522 nm≦λ₂≦525 nm, and the wavelength λ₃ of the fluorescent light is 650nm.

Therefore, the white light emitting diode module 1 of the presentinvention mixes the first light emitting source, the second lightemitting source and the fluorescent light according to the wavelengthsand the ratio of light emitting surface areas to produce a white lightsource with higher color saturation.

Therefore, the white light emitting diode module 1 of the presentinvention can have a color saturation up to 98% and a light emittingefficiency falling within a range of 55˜60 lm/W to obtain a better whitelight source, and thus can be applied to various types of backlightmodules or illumination equipments.

With reference to FIG. 2 for a schematic view of a white light emittingdiode module of the second preferred embodiment of the presentinvention, the white light emitting diode module 2 comprises aconducting wire frame 11, a first primary color chip 12, a secondprimary color chip 13 and a phosphor layer 14. The conducting wire frame11 has an accommodating groove. The first primary color chip 12 and thesecond primary color chip 13 can be blue LED chip and green LED chiprespectively, wherein the first primary color chip 12 is installed inthe accommodating groove of the conducting wire frame 11, and the secondprimary color chip 13 is stacked on top of the first primary color chip12. It is noteworthy to be noted that the first primary color chip 12has a plurality of bumps, and the bumps are attached in theaccommodating groove of the conducting wire frame 11, such that positiveand negative electrodes of the conducting wire frame 11 can be coupledto the bumps to conduct the first primary color chip 12 and theconducting wire frame 11. The second primary color chip 13 is coupled tothe positive and negative electrodes of the conducting wire frame 11 bya plurality of conducting wires 131, and the conducting wires 131 can begold wires, but the invention is not limited to gold wires only.Therefore, the number of conducting wires 131 used can be reduced tolower the cost and simplify the manufacturing procedure. The phosphorlayer 14 is disposed in the accommodating groove of the conducting wireframe 11 and covered onto the first primary color chip 12 and the secondprimary color chip 13.

The first primary color chip 12 has a light emitting surface area A₁,and the second primary color chip 13 has a light emitting surface areaA₂, and the ratio of the light emitting surface area A₁ to the lightemitting surface area A₂ of the present invention is 0.5≦A₁/A₂≦2. It isnoteworthy to be noted that the ratio of the light emitting surface areaA₁ of the first primary color chip 12 to the light emitting surface areaA₂ of the second primary color chip 13 of this preferred embodiment ispreferably 0.5≦A₁/A₂<1.

With reference to FIG. 3 for a schematic view of a white light emittingdiode module of the third preferred embodiment of the present invention,the white light emitting diode module 3 comprises a conducting wireframe 11, a first primary color chip 12, a second primary color chip 13and a phosphor layer 14. The conducting wire frame 11 has anaccommodating groove 110. The first primary color chip 12 has aplurality of bumps attached onto the bottom of the accommodating groove110 of the conducting wire frame 11. Although the bumps are not shown inthe figure, the bumps exist and attach the bottom of the accommodatinggroove 110.

The first primary color chip 12 has a light emitting surface area A₁,and the first primary color chip 12 transmits a first light emittingsource with a wavelength λ₁, and 380 nm≦λ₁≦470 nm. The second primarycolor chip 13 is coupled to positive and negative electrodes of theconducting wire frame 11 by a plurality of conducting wires 131 andstacked on top of the first primary color chip 12, and has a lightemitting surface area A₂, and the second primary color chip 13 transmitsa second light emitting source with a wavelength λ₂, and 500 nm≦λ₂≦550nm.

The phosphor layer 14 is a phosphor plate, and the phosphor plate isattached onto the second primary color chip 13 and has a light emittingsurface area A₃, and the phosphor plate is excited to produce a redfluorescent light with a wavelength λ₃, and 600 nm≦λ₁≦670 nm.

Preferably, the first light emitting source has the wavelength λ₁ and450 nm≦λ₁≦452 nm, and the second light emitting source has thewavelength λ₂ and 522 nm≦λ₂≦525 nm, and the fluorescent light has thewavelength λ₃ of 650 nm in this preferred embodiment.

Since the first primary color chip 12, the second primary color chip 13and the phosphor layer 14 have light emitting surface areas that affectthe light mixing effect, therefore the light emitting surface areas ofthe first primary color chip 12, the second primary color chip 13 andthe phosphor layer 14 of the present invention satisfy the followingrelation:

0.5≦A ₁ /A ₂≦2;

and

0.8≦A ₃ /A ₂≦1.

In this preferred embodiment, the ratio of the light emitting surfacearea A₁ of the first primary color chip 12 to the light emitting surfacearea A₂ of the second primary color chip 13 is 0.5≦A₁/A₂≦1, and theratio of the light emitting surface area A₂ of the second primary colorchip 13 to the light emitting surface area A₃ of the phosphor layer 14is preferably 1, but the invention is not limited to such arrangementonly.

In this preferred embodiment, the phosphor layer 14 is adhered onto thesecond primary color chip 13, so as to reduce the material consumptionand the cost of the phosphor layer 14.

With reference to FIG. 4 for a schematic view of a white light emittingdiode module of the fourth preferred embodiment of the presentinvention, the white light emitting diode module 4 comprises aconducting wire frame 11, a first primary color chip 12, a secondprimary color chip 13 and a phosphor layer 14. The conducting wire frame11 has an accommodating groove 110. The first primary color chip 12 hasa plurality of bumps attached in the accommodating groove 110 of theconducting wire frame 11 and has a light emitting surface area A₁. Thesecond primary color chip 13 is coupled to positive and negativeelectrodes of the conducting wire frame 11 by a plurality of conductingwires 131 and stacked on top of the first primary color chip 12, and thesecond primary color chip 13 has a light emitting surface area A₂.

In the present invention, the light emitting surface area A₁ of thefirst primary color chip 12 and the light emitting surface area A₂ ofthe second primary color chip 13 satisfy the following relation:

0.5≦A ₁ /A ₂≦2.

In this preferred embodiment, the ratio of the light emitting surfacearea A₁ of the first primary color chip 12 to the light emitting surfacearea A₂ of the second primary color chip 13 is preferably 0.5≦A₁/A₂<1.

The phosphor layer 14 is formed on the first primary color chip 12 andthe second primary color chip 13 by physical vapor deposition andcovered onto the first primary color chip 12 and the second primarycolor chip 13.

It is noteworthy to be noted that the first primary color chip 12 has aplurality of bumps attached in the accommodating groove 110 of theconducting wire frame 11, and the second primary color chip 13 iscoupled to positive and negative electrodes of the conducting wire frame11 by a plurality of conducting wires 131. Preferably, the conductingwires 131 are gold wires.

Therefore, the number of gold wires used in the white light emittingdiode module 4 of the present invention can be reduced to lower the costand simplify the manufacturing procedure.

With reference to FIG. 5 for a schematic view of a white light emittingdiode module of the fifth preferred embodiment of the present invention,the white light emitting diode module 5 comprises a conducting wireframe 11, a first primary color chip 12, a second primary color chip 13and a phosphor layer 14. The conducting wire frame 11 has anaccommodating groove 110, and the conducting wire frame 11 includes abridge 111. The first primary color chip 12 and the second primary colorchip 13 are blue LED chip and green LED chip, wherein the first primarycolor chip 12 is installed within the bridge 111 and fixed to the bottomof the accommodating groove 110 of the conducting wire frame 11. Thefirst primary color chip 12 has a light emitting surface area A₁, andthe first primary color chip 12 transmits a first light emitting sourcewith a wavelength λ₁, and 380 nm≦λ₁≦470 nm.

The second primary color chip 13 is installed at the top of the firstprimary color chip 12, and both sides of the second primary color chip13 are set on the bridge 111, so that when the second primary color chip13 emits light, the bridge 111 can be used for dissipating heat, so asto improve the heat dissipation speed and effect. The second primarycolor chip 13 has a light emitting surface area A₂, and the secondprimary color chip 13 emits a second light emitting source with awavelength λ₂, and 500 nm≦λ₂≦550 nm. Wherein, the light emitting surfacearea A₁ of the first primary color chip 12 is smaller than the lightemitting surface area A₂ of the second primary color chip 13. In thepresent invention, the light emitting surface area A₁ the first primarycolor chip 12 and the light emitting surface area A₂ of the secondprimary color chip 13 satisfy the following relation:

0.5≦A ₁ /A ₂≦2.

In this preferred embodiment, the ratio of the light emitting surfacearea A₁ of the first primary color chip 12 to the light emitting surfacearea A₂ of the second primary color chip 13 is preferably 1≦A₁/A₂≦2.

According to the first to fifth preferred embodiments, the presentinvention also provides the sixth to tenth preferred embodiments asexamples for a further description of the invention

With reference to FIG. 6 for a schematic view of a white light emittingdiode module of the sixth preferred embodiment of the present invention,the white light emitting diode module 6 comprises a conducting wireframe 21, a first primary color chip 23, a second primary color chip 22and a phosphor layer 24. The conducting wire frame 21 has anaccommodating groove 210 formed by stamping a metal and electroplated toenhance the surface corrosion resistance and the solderability, andfinally manufactured by plastic injection molding.

The first primary color chip 23 and the second primary color chip 22 aregreen LED chip and blue LED chip respectively, wherein the first primarycolor chip 23 is installed at of the bottom of the middle of theaccommodating groove 210 of the conducting wire frame 2 and has a lightemitting surface area A₁, and the first primary color chip 23 emits afirst light emitting source with a wavelength λ₁, and 500 nm≦λ₁≦550 nm.The second primary color chip 22 is stacked on top of the first primarycolor chip 23 and has a light emitting surface area A₂, and the secondprimary color chip 22 transmits a second light emitting source with awavelength λ₂, and 380 nm≦λ₂≦470 nm.

Wherein, the first primary color chip 23 and the second primary colorchip 22 are coupled to positive and negative electrodes of theconducting wire frame 21 by a plurality of conducting wires 221, 231respectively. Preferably, the conducting wires 221, 231 are gold wires.

The phosphor layer 24 is disposed in the accommodating groove 210 andcovered onto the first primary color chip 23 and the second primarycolor chip 22, and excited to produce red fluorescent light with awavelength λ₃, and 600 nm≦λ₃≦670 nm.

Preferably, the first light emitting source has the wavelength λ₁,wherein 522 nm≦λ₁≦525 nm, the second light emitting source has thewavelength λ₂, wherein 450 nm≦λ₂≦452 nm, the fluorescent light has thewavelength λ₃ equal to 650 nm. In the present invention, the lightemitting surface areas of the first primary color chip 23 and the secondprimary color chip 22 satisfy the following relation:

0.5≦A ₁ /A ₂≦2.

In this preferred embodiment, the ratio of the light emitting surfacearea A₁ of the first primary color chip 23 to the light emitting surfacearea A₂ of the second primary color chip 22 is preferably 0.5≦A₁/A₂<1.

With reference to the following table for the measurement ofchromaticity of the white light emitting diode module 6 of the presentinvention, the white light emitting diode module 6 together with a colorfilter are used to measure the RGB chromaticity coordinate values of thewhite light emitting diode module 6.

TABLE 1 CIE xy chromaticity coordinate Light Source X-coordinateY-coordinate Red 0.6719 0.3131 Green 0.2181 0.6955 Blue 0.1536 0.0661

From the x-coordinate and y-coordinate, the magnitude and the shape ofcolor gamut can be determined, so that the white light emitting diodemodule 6 of the present invention can produce a white light source withhigher color saturation based on the wavelengths and the ratio of thelight emitting surface areas.

In this preferred embodiment, the color saturation of the white lightemitting diode module 6 is up to 98.06% when chromaticity coordinatesdefined by NTSC or the color saturation of the white light emittingdiode module 6 is up to 97.61% when chromaticity coordinates defined byAdobe RGB respectively, and the light emitting efficiency of white lightemitting diode module 6 falls within a range of 55-60 lm/W.

With reference to FIG. 7 for a schematic view of a white light emittingdiode module of the seventh preferred embodiment of the presentinvention, the white light emitting diode module 7 comprises aconducting wire frame 21, a first primary color chip 23, a secondprimary color chip 22 and a phosphor layer 24. The conducting wire frame21 has an accommodating groove. The first primary color chip 23 isinstalled at the bottom of the accommodating groove of the conductingwire frame 21, and the second primary color chip 22 is stacked on top ofthe first primary color chip 23, and the phosphor layer 24 is disposedin the accommodating groove of the conducting wire frame 21 and coveredonto the first primary color chip 23 and the second primary color chip22.

The difference between this preferred embodiment and the first preferredembodiment resides on that the first primary color chip 23 has aplurality of bumps attached onto the bottom of the conducting wire frame21, and the second primary color chip 22 is coupled to positive andnegative electrodes of the conducting wire frame 21 by a plurality ofconducting wires 231. Therefore, the number of conducting wires 231 usedcan be reduced to lower the cost and simplify the manufacturingprocedure.

With reference to FIG. 8 for a schematic view of a white light emittingdiode module of the eighth preferred embodiment of the presentinvention, the white light emitting diode module 8 comprises aconducting wire frame 21, a first primary color chip 23, a secondprimary color chip 22 and a phosphor layer 24. The conducting wire frame21 has an accommodating groove 210. The first primary color chip 23 andthe second primary color chip 22 are green LED chip and blue LED chiprespectively, wherein the first primary color chip 23 has a plurality ofbumps attached in the accommodating groove 210 of the conducting wireframe 21, and the first primary color chip 23 has a light emittingsurface area A₁, and the first primary color chip 23 transmits a firstlight emitting source with a wavelength λ₁, and 500 nm≦λ₁≦550 nm. Thesecond primary color chip 22 is coupled to positive and negativeelectrodes of the conducting wire frame 21 by a plurality of conductingwires 231 and stacked on top of the first primary color chip 23 and hasa light emitting surface area A₂, and the second primary color chip 22transmits a second light emitting source with a wavelength λ₃, and 380nm≦λ₂≦470 nm.

The phosphor layer 24 is a phosphor plate attached onto the secondprimary color chip 22 and having a light emitting surface area A₃, andexcited to produce red fluorescent light with a wavelength λ₃, and 600nm≦λ₃≦670 nm.

Preferably, the first light emitting source has the wavelength λ₁wherein 522 nm≦λ₁≦525 nm, the second light emitting source has thewavelength λ₂ wherein 450 nm≦λ₂≦452 nm, and the fluorescent light hasthe wavelength λ₃ equal to 650 nm in this preferred embodiment.

Since the first primary color chip 23, the second primary color chip 22and the phosphor layer 24 have light emitting surface areas that affectthe light mixing effect, therefore the light emitting surface areas ofthe first primary color chip 23, the second primary color chip 22 andthe phosphor layer 24 of the present invention satisfy the followingrelation:

0.5≦A ₁ /A ₂≦2;

0.8≦A ₃ /A ₂≦1.

In this preferred embodiment, the ratio of the light emitting surfacearea A₁ of the first primary color chip 23 to the light emitting surfacearea A₂ of the second primary color chip 22 is preferably 0.5≦A₁/A₂<1.In addition, the phosphor layer 24 is attached onto the second primarycolor chip 22, so that the material consumption of the phosphor layer 24can be reduced to lower the cost and expense.

With reference to FIG. 9 for a schematic view of a white light emittingdiode module of the ninth preferred embodiment of the present invention,the white light emitting diode module 9 comprises a conducting wireframe 21, a first primary color chip 23, a second primary color chip 22and a phosphor layer 24. The conducting wire frame 21 has anaccommodating groove 210. The first primary color chip 23 has aplurality of bumps attached onto the bottom of the accommodating groove210 of the conducting wire frame 21 and a light emitting surface areaA₁. The second primary color chip 22 is coupled to positive and negativeelectrodes of the conducting wire frame 21 by a plurality of conductingwires 231, and the second primary color chip 22 is stacked on top of thefirst primary color chip 23 and has a light emitting surface area A₂.

In the present invention, the light emitting surface area A₁ of thefirst primary color chip 23 and the light emitting surface area A₂ ofthe second primary color chip 22 satisfy the following relation:

0.5≦A ₁ /A ₂≦2.

In this preferred embodiment, the ratio of the light emitting surfacearea A₁ of the first primary color chip 23 to the light emitting surfacearea A₂ of the second primary color chip 22 is preferably 0.5≦A₁/A₂<1.

The phosphor layer 24 is coated and encapsulated on the first primarycolor chip 23 and the second primary color chip 22 and covered onto thefirst primary color chip 23 and the second primary color chip 22.

It is noteworthy to be noted that the first primary color chip 23 has aplurality of bumps attached in the accommodating groove 210 of theconducting wire frame 21, and the second primary color chip 22 iscoupled to positive and negative electrodes of the conducting wire frame21 by a plurality of conducting wires 231. Preferably, the conductingwires 231 are gold wires.

Therefore, the number of gold wires used in the white light emittingdiode module 9 of the present invention can be reduced to lower the costand simplify the manufacturing procedure.

With reference to FIG. 10 for a schematic view of a white light emittingdiode module of the tenth preferred embodiment of the present invention,the white light emitting diode module 10 comprises a conducting wireframe 21, a first primary color chip 23, a second primary color chip 22and a phosphor layer 24. The conducting wire frame 21 has anaccommodating groove, and the conducting wire frame 11 includes a bridge211. The first primary color chip 23 and the second primary color chip22 re green LED chip and blue LED chip respectively, wherein the firstprimary color chip 23 is installed within the bridge 211 and fixed tothe bottom of the accommodating groove of the conducting wire frame 21.The first primary color chip 23 has a light emitting surface area A₁,and the first primary color chip 23 transmits a first light emittingsource with a wavelength λ₁, and 500 nm≦λ₁≦550 nm.

The second primary color chip 22 is installed at the top of the firstprimary color chip 23, and both sides of the second primary color chip22 are set on the bridge 211, so that when the second primary color chip22 emits light, the bridge 211 can be used for dissipating heat toimprove the heat dissipation speed and effect of the second primarycolor chip 22.

The second primary color chip 22 has a light emitting surface area A₂,and the second primary color chip 22 transmits a second light emittingsource with a wavelength λ₂, and 380 nm≦λ₂≦470 nm. Wherein, the firstprimary color chip 23 has a light emitting surface area A₁ smaller thanthe light emitting surface area A₂ of the second primary color chip 22,and the light emitting surface area A₁ of the first primary color chip23 and the light emitting surface area A₂ of the second primary colorchip 22 satisfy the following relation:

0.5≦A ₁ /A ₂≦2.

In this preferred embodiment, the ratio of the light emitting surfacearea A₁ of the first primary color chip 23 to the light emitting surfacearea A₂ of the second primary color chip 22 is preferably 1≦A₁/A₂≦2.

It is noteworthy to be noted that if the first primary color chip is ablue LED chip, and the second primary color chip is a green LED chip,blue light cannot penetrate through the LED chip at the top easily, andit is necessary to increase the current that passes through the firstprimary color chip in order to enhance the brightness of the firstprimary color chip, in addition to the first to tenth preferredembodiments as described above.

What is claimed is:
 1. A white light emitting diode module, comprising:a conducting wire frame, having an accommodating groove; a first primarycolor chip, installed at the bottom of the middle of the accommodatinggroove, and having a light emitting surface area A₁, and transmitting afirst light emitting source with a wavelength λ₁, and 380 nm≦λ₁≦470 nm;a second primary color chip, stacked on top of the first primary colorchip, and having a light emitting surface area A₂, and transmitting asecond light emitting source with a wavelength λ₂, and 500 nm≦λ₂≦550 nm;and a phosphor layer, disposed on the second primary color chip, andexcited to produce a fluorescent light with a wavelength λ₃, and 600nm≦λ₃≦670 nm; wherein, the light emitting surface area A₁ of the firstprimary color chip and the light emitting surface area A₂ the secondprimary color chip satisfy the relation of 0.5≦A₁/A₂≦2.
 2. The whitelight emitting diode module of claim 1, wherein the phosphor layer isfilled and disposed in the accommodating groove and covered onto thefirst primary color chip and the second primary color chip.
 3. The whitelight emitting diode module of claim 1, wherein the phosphor layer is aphosphor plate attached onto the second primary color chip and having alight emitting surface area A₃, and the light emitting surface area A₂of the second primary color chip and the light emitting surface area A₃of the phosphor plate satisfy the relation of 0.8≦A₃/A₂≦1.
 4. The whitelight emitting diode module of claim 1, wherein the phosphor layer isformed on the first primary color chip and the second primary color chipby physical vapor deposition.
 5. The white light emitting diode moduleof claim 1, wherein the first primary color chip and the second primarycolor chip are coupled to positive and negative electrodes of theconducting wire frame by a plurality of conducting wires respectively.6. The white light emitting diode module of claim 1, wherein the firstprimary color chip has a plurality of bumps attached in theaccommodating groove of the conducting wire frame, and the secondprimary color chip is coupled to positive and negative electrodes of theconducting wire frame by a plurality of conducting wires.
 7. A whitelight emitting diode module, comprising: a conducting wire frame, havingan accommodating groove; a first primary color chip, installed at thebottom of the middle of the accommodating groove, and having a lightemitting surface area A₁, and the first primary color chip transmittinga first light emitting source with a wavelength λ₁, and 500 nm≦λ₁≦550nm; a second primary color chip, stacked on top of the first primarycolor chip, and having a light emitting surface area A₂, andtransmitting a second light emitting source with a wavelength λ₂, and380 nm≦λ₂≦470 nm, and the first light emitting source and the secondlight emitting source being mixed to form a stacked light source; and aphosphor layer, disposed on the second primary color chip, and emittinga fluorescent light with a wavelength λ₃, and 600 nm≦λ₃≦670 nm; wherein,the light emitting surface area A₁ of the first primary color chip andthe light emitting surface area A₂ the second primary color chip satisfythe relation of 0.5≦A₁/A₂≦2.
 8. The white light emitting diode module ofclaim 7, wherein the phosphor layer is filled and disposed in theaccommodating groove, and covered onto the first primary color chip andthe second primary color chip.
 9. The white light emitting diode moduleof claim 7, wherein the phosphor layer is a phosphor plate attached ontothe second primary color chip and having a light emitting surface areaA₃, and the light emitting surface area A₂ of the second primary colorchip and the light emitting surface area A₃ of the phosphor platesatisfy the relation of 0.8≦A₃/A₂≦1.
 10. The white light emitting diodemodule of claim 7, wherein the phosphor layer is formed on the firstprimary color chip and the second primary color chip by physical vapordeposition.
 11. The white light emitting diode module of claim 7,wherein the first primary color chip and the second primary color chipare coupled to positive and negative electrodes of the conducting wireframe by a plurality of conducting wires respectively.
 12. The whitelight emitting diode module of claim 7, wherein the first primary colorchip has a plurality of bumps attached in the accommodating groove ofthe conducting wire frame, and the second primary color chip is coupledto positive and negative electrodes of the conducting wire frame by aplurality of conducting wires.